Lo tossed 19 1/3 innings out of the bullpen for the Astros last season, posting an ERA of 4.19. He struck out 7.4 batters per nine innings but allowed a 6.1 BB/9. The 28-year-old has a strong track record of missing bats in the minors, averaging an even 10 strikeouts per 9 over 129 career innings there.